Energy Performance Research Articles

Application of Internet of Things (IoT) in Energy Infrastructure: Lessons for the Future of Operations and Maintenance

The application of the Internet of Things (IoT) in energy infrastructure is revolutionizing operations and maintenance practices, driving efficiencies, and enhancing sustainability across the sector. This paper explores the transformative impact of IoT technologies on energy infrastructure, focusing on how they facilitate real-time monitoring, predictive maintenance, and data-driven decision-making. By leveraging IoT devices and systems, energy operators can optimize performance, reduce operational costs, and minimize downtime, ultimately contributing to more resilient and sustainable energy systems. The discussion highlights key IoT applications within energy infrastructure, including smart grids, renewable energy systems, and conventional power plants. Smart sensors and devices enable continuous data collection, providing insights into equipment performance, energy consumption, and environmental conditions. Predictive analytics, powered by IoT data, allows operators to anticipate equipment failures and conduct maintenance proactively, thereby extending asset life and improving reliability. Additionally, the abstract addresses the challenges associated with IoT integration in energy infrastructure, such as cybersecurity risks, data management issues, and the need for interoperability among diverse systems. It emphasizes the importance of establishing robust security protocols to protect sensitive data and ensure the integrity of IoT networks. Furthermore, the role of regulatory frameworks and industry standards in promoting the safe and effective deployment of IoT technologies is discussed. The paper also examines case studies of successful IoT implementations in energy infrastructure, showcasing the lessons learned from these initiatives. These examples illustrate the potential for IoT to enhance operational efficiency, reduce greenhouse gas emissions, and support the transition to cleaner energy sources. In conclusion, the abstract underscores that the adoption of IoT technologies in energy infrastructure is not just a trend but a necessity for the future of operations and maintenance. As the energy sector continues to evolve, embracing IoT will be crucial for achieving sustainability goals and meeting the growing demands for reliable energy supply.

Calculation of exergy losses, exergy efficiency and cooling coefficient of refrigerant R22

This study presents a detailed analysis of the exergy losses, exergy efficiency, and cooling coefficient of performance (COP) for the refrigerant R22 in refrigeration systems. Exergy analysis, which considers both the quantity and quality of energy, is used to identify and quantify the irreversibilities within the system. The objective of this analysis is to provide insights into the areas of inefficiency and potential improvements for enhanced energy performance. Results indicate that the exergy losses in R22 systems are primarily associated with the compressor and expansion valve, highlighting these components as key targets for efficiency improvements. The exergy efficiency was found to vary significantly with operating conditions, suggesting that system performance could be optimized through appropriate design and control strategies. Additionally, the cooling COP of R22 was evaluated, demonstrating its effectiveness in converting input energy into cooling capacity under various conditions. This analysis contributes to the broader understanding of R22's thermodynamic performance and offers a foundation for developing more sustainable and efficient refrigeration technologies.

Application of a decision tree approach to predict energy consumption in lightweight buildings under subtropical climate

PurposeLightweight building systems have emerged as alternatives to reduce the high environmental impact of conventional masonry. However, in subtropical climates, the low thermal inertia of lightweight envelopes negatively affects energy performance. The purpose of this paper is to investigate the thermophysical parameters that influence heating and cooling energy consumption in lightweight residential buildings under subtropical climates and develop a model to predict these parameters using statistical and machine learning tools.Design/methodology/approachA database was created with computer simulation data on the energy performance of 2048 building conditions generated by factorial combination of 10 parameters. Sensitivity analysis was performed to identify which parameters contribute most to energy performance indicators. Subsequently, decision trees were created using a classification and regression tree (CART) algorithm to visualize parameters and improve energy performance indicators, particularly cooling energy consumption.FindingsLow thermal transmittance and ground contact are interesting strategies for low thermal capacity buildings. Furthermore, the findings showed that relying only on the most influential properties does not ensure good energy performance; rather, it is the adequate combination of envelope properties that leads to good energy efficiency. The tree developed by CART can be used as a guide to assist designers and researchers in the initial selection of building envelopes, demonstrating the impact of each choice on electrical energy consumption for indoor climate control.Originality/valueBy adopting a global approach to assess the thermal performance of lightweight buildings, this study makes a significant contribution to synthesizing the results of a complex and time-consuming methodology into a guide for optimizing envelope design decisions and directing efforts and resources toward efficient strategies.

Wind-Solar-Thermal Power Coupling System in The Power Market Environment Benefit Distribution Studies

With the continuous increase in the proportion of new energy, China’s power system will further increase the capacity and flexibility of new energy consumption capacity and flexibility in the future. The combined operation of renewable energy and thermal power can improve the utilization rate of renewable energy and the economy of thermal power operation to a certain extent, and is one of the effective ways to solve the problem of curtailment of wind and solar power. Based on the combing of the market mode of wind-solar-thermal coupling system, this paper discusses the game relationship between wind power, photovoltaic power and thermal power, and proposes the operation strategy of wind-solar-thermal power coupling system under the spot market; Then, with the goal of maximizing economic benefits, a two-stage stochastic optimization model was constructed in the coupled operation mode and the independent operation mode, respectively, and the contribution of the alliance members in the day-ahead market, flexibility contribution and environmental cost contribution was weighed, and the revenue distribution method between renewable energy and thermal power was proposed by introducing the market contribution index; Finally, based on the simulation and verification of a local power grid in Liaoning Province, the results show that the proposed joint operation strategy effectively improves the overall revenue level, and proposes a gain cooperative revenue distribution strategy with computational efficiency, which fully considers the contribution of each entity to the alliance for fair distribution, and is conducive to guiding the coordinated development of new energy and thermal power.

Configurational Design of a Hybrid System Based on an Air–Water Heat Pump and Biomass Boiler for a Rural Dwelling

Hybrid energy systems combine multiple energy sources and storage technologies to enhance performance and meet diverse energy needs. Hybrid heat pump systems are particularly suitable for heating and cooling buildings in rural areas. Air-source heat pumps have two well-known disadvantages during the coldest period of the year, when the building’s heating load is at its peak: the heat pump’s capacity is reduced and it needs to perform defrost cycles. A potential solution is to size the heat pump to cover only a portion of the peak load and to use a second heat generator in a hybrid heat pump system. There is a gap in the literature regarding the configurational analysis of hybrid heat pump (HHP) systems, particularly in terms of combining heat pumps and biomass boilers, and evaluating their efficiency, economic aspects, and environmental impact. Thus, in this research, a dynamic model of a HHP system, consisting of an air-to-water heat pump paired with a biomass boiler as a backup, is presented. Various configurations of the HHP system have been developed to evaluate key performance indicators, such as efficiency, emissions, operational costs, and other relevant factors. The findings of this paper indicate that the energy performance of HHP systems is significantly affected by the system layout, heat pump size, cut-off temperature, and the control algorithm used to activate the heat generators. Moreover, series operation of HHP systems is not only more efficient than parallel operation but also results in lower emissions and reduced operation costs. As expected, the energy loss associated with defrost cycles significantly impacts the overall performance of a hybrid system based on an air-source heat pump. Finally, the impact of the cut-off temperature on the key parameters in the configuration analysis was examined, and the optimal performance of the HHP system, in terms of minimizing operational costs and emissions, was depicted using a heat map diagram.

IBIS ECO PLATFORM: A Decision Support System for Monitoring and Managing the Energy Performance and Comfort of Existing Buildings

IBIS ECO PLATFORM: A Decision Support System for Monitoring and Managing the Energy Performance and Comfort of Existing Buildings

Evaluating the Effect of Adaptive Reuse in the Energy Performance of Historic Buildings: A Case Study from Türkiye

The building sector accounts for 30% to 40% of total energy consumption, and historic buildings play an important role in this proportion. Historical buildings that do not meet the required comfort conditions for the residents are adaptively reused, with various revisions. Recognizing the energy design of a historical building in its original condition and comparing the current situation can help create future solutions. This study examines the changes that a historic house in a hot climate zone in Türkiye experiences, from its original state up until the current situation. Energy analyses of the pre- and post-restoration situation are carried out, and the effect of adaptive reuse decisions on the energy performance of the building is investigated. A dynamic thermal simulation created with DesignBuilder was used to identify the energy use, carbon emissions, and thermal comfort. TM59 adaptive thermal comfort was used for the pre-restoration and the Fanger model for the post-restoration phase. This building, which was repurposed from a three-block residence, consists of a four-block hotel. Although the preservation of its original value is at the forefront, various structural changes were observed. The analysis demonstrates a higher occurrence of discomfort hours during summer compared to winter, consistent across both phases. Furthermore, energy consumption increased significantly, predominantly for heating, representing a doubling of energy use during the post-restoration phase. This is attributed to the building’s conversion into a hotel and the use of mechanical systems. Future research is required to develop strategies to reduce the energy consumption, carbon emissions, and discomfort hours while maintaining the value of the historic building and its materials.

Digital Twins for Reducing Energy Consumption in Buildings: A Review

This research investigates the use of digital twin (DT) technology to improve building energy management and analyse occupant behaviour. DTs perform the function of acting as virtual replicas of physical assets, which facilitates real-time monitoring, predictive maintenance, and data-driven decision-making. Consequently, energy performance and occupant comfort can be enhanced. This study evaluates the efficiency of DTs in optimising energy usage by a mix of a systematic literature review and scientometric analysis of 466 articles from the Scopus database. Among the main obstacles noted are interoperability issues, privacy and data quality difficulties, and the requirement for a more thorough integration of digital and physical interactions. The results highlight the necessity of standardised frameworks to direct DT implementations and suggest areas for further study, especially in the areas of improving cybersecurity and incorporating occupant behaviour into DT models. This research makes practical recommendations for using DT technology to increase energy efficiency and sustainability in the built environment.

Thermo-economic analysis on trans-critical compressed CO2 energy storage system integrated with the waste heat of liquid-cooled data center

Compressed CO2 energy storage (CCES) technology has the advantages of high energy storage density, low economic cost, low carbon emission, which is suitable for the construction of large-scale and long-time energy storage system. Besides, as a scene with massive heat, the electricity consumption of servers in data center is mostly converted into heat. Thus, the purpose of this work is to integrate a trans-critical compressed CO2 energy storage system with the waste heat of data centers, so as to improve the system performance and reduce the operating cost of data center. Based on different operating principles of compressors, a single-stage compression system (System-CP) and a double-stage compression system (System-VP) are constructed. To analyze and compare the energy and exergy performance of these two systems under design conditions, a quasi-dynamic model is developed by considering the variations of pressure and temperature in the storage tank. On this basis, an economic model is developed to obtain the economy performance for the systems. The obtained results show that the round-trip efficiency (RTE) of System-CP and System-VP are 64.67 % and 67.41 %, respectively. For the energy storage capacity 15 MW × 5 h, volumes of high-pressure S-CO2 storage tank are 314,387.51 m3 and 287,982.91 m3 for System-CP and System-VP, respectively. Thereby, the energy storage density (ESD) of System-CP and System-VP are 0.24 kW·h/m3 and 0.26 kW·h/m3, respectively. Meanwhile, the total capital cost (TCC) is $477.84 × 106 for System-CP, and $437.41 × 106 for System-VP, and the corresponding payback period (PBP) are 14.76 years and 12.39 years respectively. Further, the effect of key parameters on systems performance is revealed. The results show that with the decrease of slip-pressure range decreases, RTE, TCC and the volume of storage tanks increase linearly.

Application of an Optimal Fractional-Order Controller for a Standalone (Wind/Photovoltaic) Microgrid Utilizing Hybrid Storage (Battery/Ultracapacitor) System

Nowadays, standalone microgrids that make use of renewable energy sources have gained great interest. They provide a viable solution for rural electrification and decrease the burden on the utility grid. However, because standalone microgrids are nonlinear and time-varying, controlling and managing their energy can be difficult. A fractional-order proportional integral (FOPI) controller was proposed in this study to enhance a standalone microgrid’s energy management and performance. An ultra-capacitor (UC) and a battery, called a hybrid energy storage scheme, were employed as the microgrid’s energy storage system. The microgrid was primarily powered by solar and wind power. To achieve optimal performance, the FOPI’s parameters were ideally generated using the gorilla troop optimization (GTO) technique. The FOPI controller’s performance was contrasted with a conventional PI controller in terms of variations in load power, wind speed, and solar insolation. The microgrid was modeled and simulated using MATLAB/Simulink software R2023a 23.1. The results indicate that, in comparison to the traditional PI controller, the proposed FOPI controller significantly improved the microgrid’s transient performance. The load voltage and frequency were maintained constant against the least amount of disturbance despite variations in wind speed, photovoltaic intensity, and load power. In contrast, the storage battery precisely stores and releases energy to counteract variations in wind and photovoltaic power. The outcomes validate that in the presence of the UC, the microgrid performance is improved. However, the improvement is very close to that gained when using the proposed controller without UC. Hence, the proposed controller can reduce the cost, weight, and space of the system. Moreover, a Hardware-in-the-Loop (HIL) emulator was implemented using a C2000™ microcontroller LaunchPad™ TMS320F28379D kit (Texas Instruments, Dallas, TX, USA) to evaluate the proposed system and validate the simulation results.

Enhancing shipboard waste heat management with advanced technologies

The complexity of the energy systems onboard ships, combined with the different operating/weather conditions and the availability of cutting-edge technologies, makes analyses for improving the energy and environmental performances of ships time consuming and challenging. From this point of view, this article provides new criteria for the sustainable design and management of energy systems of existing or new ships. In particular, the impact of the adoption of organic Rankine cycle units, wet steam volumetric expanders, and single or double effect absorption chillers is here investigated. Two types of ships are examined as suitable case studies, evaluating the impact of each technology and their combinations by varying the shipping cruises. By using a dynamic simulation approach, potential savings and optimal solutions are assessed for different energy system layouts by also comparing their economic, energy and environmental impact performance. Results are reported in specific performance matrices for helping stakeholders in preliminary energy efficiency analyses.In particular, outcomes show that high cooling demands of ships in the Caribbean Sea enable primary energy savings close to 4.5 %, compared to 3.5 % in the Mediterranean Sea and 3 % in the North Sea. In the latter case, cooling needs can be almost fully balanced through the examined energy recovery technologies. Screw expanders integrate best in all operating conditions with short paybacks, whilst organic Rankine cycles (with electrical efficiency above 8%) are advantageous especially in cold climate routes. Benefits on environmental impact are significant, with avoided CO2 emissions around 6 kt/y, depending on the selected ship cruise.

Understanding the Integration of Building Energy Modeling into the Building Design Process: Insights from Two Collaborative Construction Projects

This research investigates the integration of building energy modeling (BEM) within collaborative construction projects to inform design decisions for achieving high-energy performance goals. The study aims to understand current practices, benefits, and challenges associated with this integration. Using an ethnographic case study approach focused on two high-energy performance social housing projects with integrated project delivery and integrated design processes, data were collected through direct observations, document analysis, and interviews with project team members. Design process modeling was utilized to dissect current practices, followed by a hybrid inductive and deductive thematic analysis to find challenges related to energy performance design in collaborative projects. Findings from this research revealed that BEM experts often operate in isolation, with late integration of energy models into design decisions. Compliance-centric BEM usage and challenges related to interoperability of design and BEM tools further compound the issue of seamless collaboration. However, the study highlights that early collaboration among project stakeholders emerges as a pivotal factor in informed design decisions, bridging the gap between energy modeling and design. This research provides valuable insights for practitioners seeking to optimize BEM in their design process, and offers support to policymakers aiming to enhance the role of BEM in projects.

Solar Species: Energy Optimization of Urban Form Through an Evolutionary Design Process

This paper proposes design guidelines to enhance energy efficiency and energy generation potential in active solar buildings. Additionally, it presents a variety of optimized urban forms characterized by attributes such as shape, layout, and number of buildings on the plot. These urban configurations are classified into solar species, each associated with a distinct range of high passive and active solar potential. These results were achieved by developing and applying a simulation-driven, multi-objective optimization technique for the early-stage design of a residential building cluster in a temperate climate. This method leverages both passive and active energy indicators, employing a genetic algorithm to identify optimal forms that maximize active solar potential while also minimizing operational energy demand. The approach utilizes a parametric modelling routine that relies on vertical cores and horizontal connections to produce design iterations featuring irregular geometry, while ensuring structural continuity and means of egress. The findings reveal a significant variability in onsite energy generation, with optimized solutions differing by a factor of 2.5 solely based on shape, underscoring the critical role of active solar potential. Taken together, these results hint at the descriptive and predictive capabilities of these solar species, making them a promising heuristic model for characterizing urban form in relation to energy performance.

The Sustainable Configuration Optimisation of Office Multi-Angled Façade Systems

This research paper optimises the configuration of multi-angled façade systems to achieve the sustainability goals of reduced energy consumption and improved indoor climate quality. The concept of a multi-angled façade system is based on proposing the use of two different orientations of windows in each façade on a vertical axis, but not tilted up and down. The large part of the multi-angled façade is oriented more to the north to optimise the use of daylight and the small part more to the south to optimise the use of solar radiation. In order to evaluate the performance of the façade, the software program IDA ICE version 4.8 is used. (EQUA, Stockholm, Sweden). Two groups of scenarios were simulated: the first group consisted of nine scenarios (A1 to A9) that included changing the area and the orientation of the two façade parts, and the second group consisted of three scenarios (B1 to B3) by changing the window to wall ratio (WWR) of these scenarios. According to the results of the simulation, two scenarios from the first group are recommended: A3 for optimal daylight penetration and A7 for optimal energy performance. Regarding the second group, scenarios B1 for optimal daylight penetration and B3 for optimal energy performance are recommended.

Assessing the Influence of Occupancy Factors on Energy Performance in US Small Office Buildings

Office buildings are responsible for about 35% of the total electricity in the US and over 70% of building energy consumption occurs during occupancy periods. Therefore, understanding occupancy behavior is crucial for reducing building energy consumption. However, given the stochastic nature of occupant behavior, identifying which occupancy parameters have the most impact on energy consumption poses a considerable challenge. This study aims to investigate and quantify the impact of various occupancy parameters on the energy performance of a US small-sized office building using an EnergyPlus-based nationwide energy simulation. First, dynamic occupancy schedules are created based on different occupancy parameters using an agent-based model. Next, the generated dynamic occupancy schedules are integrated into a small office building model from the Department of Energy’s prototypes. This creates a dataset of occupancy parameters and building energy performance across various climate zones. Finally, various feature selection and statistical analysis methods are applied to the generated dataset. This helps identify significant occupancy parameters and quantify their impact on building energy performance across different climate zones. According to the results of the study, buildings located in cool marine, mixed marine, and warm marine climate zones had lower total energy consumption compared to other zones. Additionally, feature selection methods identified “Occupant Density” as the primary significant variable impacting energy consumption, across all climate zones. These findings offer valuable insights into the influential occupancy parameters across various climate zones, highlighting the importance of tailoring occupancy schedules to enhance energy efficiency. They provide practical guidance that can be directly applied to optimize energy consumption and achieve significant energy savings in small office settings with different weather conditions.

Enhancing financial reporting and management efficiency through enterprise resource planning (ERP) systems: A theoretical review for large-scale energy operations

Enterprise Resource Planning (ERP) systems have emerged as essential tools in streamlining financial reporting and improving management efficiency across various industries, including large-scale energy operations. This theoretical review explores how ERP systems enhance financial reporting by integrating real-time data, automating financial processes, and fostering transparency. In energy operations, where financial activities are complex and data-intensive, ERP systems centralize financial data, reducing errors, improving compliance, and supporting decision-making through enhanced visibility and accuracy. By automating tasks such as budgeting, forecasting, and financial statement generation, ERP systems enable energy companies to efficiently manage their financial resources, thus optimizing cost control and profitability. Additionally, ERP systems provide significant benefits for management efficiency, particularly in large-scale operations. The integration of financial, operational, and managerial processes within a single platform allows for better resource allocation, improved communication across departments, and faster response times to market fluctuations. These capabilities are crucial in the energy sector, where companies face volatile market conditions, regulatory pressures, and high operational risks. ERP systems enhance managerial decision-making by providing real-time insights into key performance indicators (KPIs), enabling executives to make data-driven decisions that support long-term strategic goals. However, implementing ERP systems in large-scale energy operations presents challenges, including high costs, lengthy implementation periods, and the need for employee training. This review also examines these barriers and suggests strategies for successful ERP adoption, including phased implementation, stakeholder engagement, and customization to industry-specific needs. In conclusion, ERP systems hold the potential to revolutionize financial reporting and management efficiency in large-scale energy operations. By leveraging ERP's real-time data integration and process automation, energy companies can significantly improve their financial management, enhance decision-making, and adapt more quickly to market changes. Keywords: ERP Systems, Financial Reporting, Management Efficiency, Large-Scale Energy Operations, Process Automation, Real-Time Data Integration, Decision-Making, Cost Control, Market Fluctuations, Energy Sector.

Performance assessment of a 30.26 kW grid-connected photovoltaic plant in Egypt

Abstract This paper presents an experimental analysis and performance evaluation of a grid-connected photovoltaic plant installed on the rooftop of the Electronics Research Institute in Cairo, Egypt. Cairo is classified as a hot-desert climate region according to the standard Koppen-Geiger climate classification system. Over a year, we monitored real-time data to assess key system performance metrics, such as energy yield, efficiencies, performance ratio, capacity factor, and losses. Based on the obtained experimental results, the highest final yield of 5.2498 hr/day was observed in the summer, whereas the lowest yield of 3.439 hr/day occurred in the winter months. The photovoltaic plant had an average annual system efficiency of 15.8%, while the photovoltaic and inverter had mean yearly efficiencies of 17.1% and 97.2%, respectively. The average annual performance ratio is 83.03%, and the capacity factor is 18.72%. The monthly total loss exhibited a linear rise alongside increasing ambient temperature and solar irradiance. The ambient temperature affected the system efficiency, photovoltaic efficiency, and performance ratio. The findings can help strengthen forecasts of future large-scale photovoltaic plants in hot desert climates. Moreover, they can guide the design, optimization, operation, and maintenance of new grid-connected photovoltaic systems.

Appraising correlation between international organisation for standardisation 50001 and green productivity: A study of workers in Baiji, Iraq

Studies have shown that the progress and success of companies are achieved through their ability to improve energy performance and preserve the environment. It would translate to environmentally friendly products. However, there is a paucity of studies regarding the International Organisation for Standardisation (ISO) 50001 and its role in enhancing environmentally friendly products in developing countries such as Iraq. This study investigates the correlation between ISO 50001 standards and green productivity among Baiji's refinery workers in Iraq. Utilising a structured questionnaire, data from 128 respondents were analysed using descriptive and inferential statistics. Results indicate a significant positive correlation between ISO 50001 and green productivity, underscoring the importance of energy management training in enhancing productivity and environmental protection. As part of the study’s implications, it suggests increasing the company’s management’s attention to training in energy management and green productivity. Its positive impact on improving productivity and protecting the environment through continuous improvement of inputs, processes, outputs, and feedback to the company cannot be overstated.

Evaluation of a Kirigami-inspired double-skin adaptive façade for natural ventilation and solar harvesting to enhance indoor environment and energy performance

A novel kirigami-inspired design concept for an environmentally responsive adaptive façade is presented and evaluated for the objectives of solar energy harvesting and adaptive ventilation through controllable surface orientation and opening. The concept is a double-skin façade where the outer skin includes a straight cut kirigami-inspired adaptive component. Controllable actuation of the kirigami-inspired section opens the outer skin for ventilation while also changing the orientation of the outer surface for solar tracking. The primary objective of this study is to evaluate the potential benefits for this concept integrated within a building façade for solar energy harvesting, air changes, and indoor temperature control. As such, a computational study is used to estimate the proposed facade concept's performance within various generalized building-environment scenarios. The methodology is detailed to computationally estimate the potential environmental performance of this concept with respect to solar harvesting with adhered solar panels, as well as air changes and HVAC cost for associated interior spaces. The example scenarios include various building components, from a single room to multiple building stories, and two geographic locations with significantly different environmental conditions, and both daily and yearly performance estimates are shown. The component is most effective when the outdoor temperature is near to the desired indoor temperature and wind speeds are mild, but can still reduce HVAC usage for more disparate temperatures. For example, in the scenarios shown the component can eliminate HVAC use for a 5°C difference between outdoor and indoor temperature and reduces HVAC usage for temperature differences up to 15°C. Moreover, the component has the potential to significantly increase net energy generation, with yearly performance estimated for the scenarios to be as much as 25% greater than that of a flat closed façade. However, the component cut parameters can have a significant impact on environmental performance, and thus require careful design consideration.

Reducing the energy performance gap through stepwise verification of building and system functions

Reducing the energy performance gap through stepwise verification of building and system functions